1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Scatterlist Cryptographic API.
5 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
6 * Copyright (c) 2002 David S. Miller (davem@redhat.com)
7 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
9 * Portions derived from Cryptoapi, by Alexander Kjeldaas <astor@fast.no>
10 * and Nettle, by Niels Möller.
13 #include <linux/err.h>
14 #include <linux/errno.h>
15 #include <linux/jump_label.h>
16 #include <linux/kernel.h>
17 #include <linux/kmod.h>
18 #include <linux/module.h>
19 #include <linux/param.h>
20 #include <linux/sched/signal.h>
21 #include <linux/slab.h>
22 #include <linux/string.h>
23 #include <linux/completion.h>
26 LIST_HEAD(crypto_alg_list
);
27 EXPORT_SYMBOL_GPL(crypto_alg_list
);
28 DECLARE_RWSEM(crypto_alg_sem
);
29 EXPORT_SYMBOL_GPL(crypto_alg_sem
);
31 BLOCKING_NOTIFIER_HEAD(crypto_chain
);
32 EXPORT_SYMBOL_GPL(crypto_chain
);
34 #ifndef CONFIG_CRYPTO_MANAGER_DISABLE_TESTS
35 DEFINE_STATIC_KEY_FALSE(__crypto_boot_test_finished
);
36 EXPORT_SYMBOL_GPL(__crypto_boot_test_finished
);
39 static struct crypto_alg
*crypto_larval_wait(struct crypto_alg
*alg
);
41 struct crypto_alg
*crypto_mod_get(struct crypto_alg
*alg
)
43 return try_module_get(alg
->cra_module
) ? crypto_alg_get(alg
) : NULL
;
45 EXPORT_SYMBOL_GPL(crypto_mod_get
);
47 void crypto_mod_put(struct crypto_alg
*alg
)
49 struct module
*module
= alg
->cra_module
;
54 EXPORT_SYMBOL_GPL(crypto_mod_put
);
56 static struct crypto_alg
*__crypto_alg_lookup(const char *name
, u32 type
,
59 struct crypto_alg
*q
, *alg
= NULL
;
62 list_for_each_entry(q
, &crypto_alg_list
, cra_list
) {
65 if (crypto_is_moribund(q
))
68 if ((q
->cra_flags
^ type
) & mask
)
71 if (crypto_is_larval(q
) &&
72 !crypto_is_test_larval((struct crypto_larval
*)q
) &&
73 ((struct crypto_larval
*)q
)->mask
!= mask
)
76 exact
= !strcmp(q
->cra_driver_name
, name
);
77 fuzzy
= !strcmp(q
->cra_name
, name
);
78 if (!exact
&& !(fuzzy
&& q
->cra_priority
> best
))
81 if (unlikely(!crypto_mod_get(q
)))
84 best
= q
->cra_priority
;
96 static void crypto_larval_destroy(struct crypto_alg
*alg
)
98 struct crypto_larval
*larval
= (void *)alg
;
100 BUG_ON(!crypto_is_larval(alg
));
101 if (!IS_ERR_OR_NULL(larval
->adult
))
102 crypto_mod_put(larval
->adult
);
106 struct crypto_larval
*crypto_larval_alloc(const char *name
, u32 type
, u32 mask
)
108 struct crypto_larval
*larval
;
110 larval
= kzalloc(sizeof(*larval
), GFP_KERNEL
);
112 return ERR_PTR(-ENOMEM
);
115 larval
->alg
.cra_flags
= CRYPTO_ALG_LARVAL
| type
;
116 larval
->alg
.cra_priority
= -1;
117 larval
->alg
.cra_destroy
= crypto_larval_destroy
;
119 strscpy(larval
->alg
.cra_name
, name
, CRYPTO_MAX_ALG_NAME
);
120 init_completion(&larval
->completion
);
124 EXPORT_SYMBOL_GPL(crypto_larval_alloc
);
126 static struct crypto_alg
*crypto_larval_add(const char *name
, u32 type
,
129 struct crypto_alg
*alg
;
130 struct crypto_larval
*larval
;
132 larval
= crypto_larval_alloc(name
, type
, mask
);
134 return ERR_CAST(larval
);
136 refcount_set(&larval
->alg
.cra_refcnt
, 2);
138 down_write(&crypto_alg_sem
);
139 alg
= __crypto_alg_lookup(name
, type
, mask
);
142 list_add(&alg
->cra_list
, &crypto_alg_list
);
144 up_write(&crypto_alg_sem
);
146 if (alg
!= &larval
->alg
) {
148 if (crypto_is_larval(alg
))
149 alg
= crypto_larval_wait(alg
);
155 void crypto_larval_kill(struct crypto_alg
*alg
)
157 struct crypto_larval
*larval
= (void *)alg
;
159 down_write(&crypto_alg_sem
);
160 list_del(&alg
->cra_list
);
161 up_write(&crypto_alg_sem
);
162 complete_all(&larval
->completion
);
165 EXPORT_SYMBOL_GPL(crypto_larval_kill
);
167 void crypto_wait_for_test(struct crypto_larval
*larval
)
171 err
= crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER
, larval
->adult
);
172 if (WARN_ON_ONCE(err
!= NOTIFY_STOP
))
175 err
= wait_for_completion_killable(&larval
->completion
);
178 crypto_larval_kill(&larval
->alg
);
180 EXPORT_SYMBOL_GPL(crypto_wait_for_test
);
182 static void crypto_start_test(struct crypto_larval
*larval
)
184 if (!crypto_is_test_larval(larval
))
187 if (larval
->test_started
)
190 down_write(&crypto_alg_sem
);
191 if (larval
->test_started
) {
192 up_write(&crypto_alg_sem
);
196 larval
->test_started
= true;
197 up_write(&crypto_alg_sem
);
199 crypto_wait_for_test(larval
);
202 static struct crypto_alg
*crypto_larval_wait(struct crypto_alg
*alg
)
204 struct crypto_larval
*larval
= (void *)alg
;
207 if (!crypto_boot_test_finished())
208 crypto_start_test(larval
);
210 timeout
= wait_for_completion_killable_timeout(
211 &larval
->completion
, 60 * HZ
);
215 alg
= ERR_PTR(-EINTR
);
217 alg
= ERR_PTR(-ETIMEDOUT
);
219 alg
= ERR_PTR(-ENOENT
);
220 else if (IS_ERR(alg
))
222 else if (crypto_is_test_larval(larval
) &&
223 !(alg
->cra_flags
& CRYPTO_ALG_TESTED
))
224 alg
= ERR_PTR(-EAGAIN
);
225 else if (alg
->cra_flags
& CRYPTO_ALG_FIPS_INTERNAL
)
226 alg
= ERR_PTR(-EAGAIN
);
227 else if (!crypto_mod_get(alg
))
228 alg
= ERR_PTR(-EAGAIN
);
229 crypto_mod_put(&larval
->alg
);
234 static struct crypto_alg
*crypto_alg_lookup(const char *name
, u32 type
,
237 const u32 fips
= CRYPTO_ALG_FIPS_INTERNAL
;
238 struct crypto_alg
*alg
;
241 if (!((type
| mask
) & CRYPTO_ALG_TESTED
))
242 test
|= CRYPTO_ALG_TESTED
;
244 down_read(&crypto_alg_sem
);
245 alg
= __crypto_alg_lookup(name
, (type
| test
) & ~fips
,
246 (mask
| test
) & ~fips
);
248 if (((type
| mask
) ^ fips
) & fips
)
252 if (!crypto_is_larval(alg
) &&
253 ((type
^ alg
->cra_flags
) & mask
)) {
254 /* Algorithm is disallowed in FIPS mode. */
256 alg
= ERR_PTR(-ENOENT
);
259 alg
= __crypto_alg_lookup(name
, type
, mask
);
260 if (alg
&& !crypto_is_larval(alg
)) {
263 alg
= ERR_PTR(-ELIBBAD
);
266 up_read(&crypto_alg_sem
);
271 static struct crypto_alg
*crypto_larval_lookup(const char *name
, u32 type
,
274 struct crypto_alg
*alg
;
277 return ERR_PTR(-ENOENT
);
279 type
&= ~(CRYPTO_ALG_LARVAL
| CRYPTO_ALG_DEAD
);
280 mask
&= ~(CRYPTO_ALG_LARVAL
| CRYPTO_ALG_DEAD
);
282 alg
= crypto_alg_lookup(name
, type
, mask
);
283 if (!alg
&& !(mask
& CRYPTO_NOLOAD
)) {
284 request_module("crypto-%s", name
);
286 if (!((type
^ CRYPTO_ALG_NEED_FALLBACK
) & mask
&
287 CRYPTO_ALG_NEED_FALLBACK
))
288 request_module("crypto-%s-all", name
);
290 alg
= crypto_alg_lookup(name
, type
, mask
);
293 if (!IS_ERR_OR_NULL(alg
) && crypto_is_larval(alg
))
294 alg
= crypto_larval_wait(alg
);
296 alg
= crypto_larval_add(name
, type
, mask
);
301 int crypto_probing_notify(unsigned long val
, void *v
)
305 ok
= blocking_notifier_call_chain(&crypto_chain
, val
, v
);
306 if (ok
== NOTIFY_DONE
) {
307 request_module("cryptomgr");
308 ok
= blocking_notifier_call_chain(&crypto_chain
, val
, v
);
313 EXPORT_SYMBOL_GPL(crypto_probing_notify
);
315 struct crypto_alg
*crypto_alg_mod_lookup(const char *name
, u32 type
, u32 mask
)
317 struct crypto_alg
*alg
;
318 struct crypto_alg
*larval
;
322 * If the internal flag is set for a cipher, require a caller to
323 * invoke the cipher with the internal flag to use that cipher.
324 * Also, if a caller wants to allocate a cipher that may or may
325 * not be an internal cipher, use type | CRYPTO_ALG_INTERNAL and
326 * !(mask & CRYPTO_ALG_INTERNAL).
328 if (!((type
| mask
) & CRYPTO_ALG_INTERNAL
))
329 mask
|= CRYPTO_ALG_INTERNAL
;
331 larval
= crypto_larval_lookup(name
, type
, mask
);
332 if (IS_ERR(larval
) || !crypto_is_larval(larval
))
335 ok
= crypto_probing_notify(CRYPTO_MSG_ALG_REQUEST
, larval
);
337 if (ok
== NOTIFY_STOP
)
338 alg
= crypto_larval_wait(larval
);
340 crypto_mod_put(larval
);
341 alg
= ERR_PTR(-ENOENT
);
343 crypto_larval_kill(larval
);
346 EXPORT_SYMBOL_GPL(crypto_alg_mod_lookup
);
348 static void crypto_exit_ops(struct crypto_tfm
*tfm
)
350 const struct crypto_type
*type
= tfm
->__crt_alg
->cra_type
;
352 if (type
&& tfm
->exit
)
356 static unsigned int crypto_ctxsize(struct crypto_alg
*alg
, u32 type
, u32 mask
)
358 const struct crypto_type
*type_obj
= alg
->cra_type
;
361 len
= alg
->cra_alignmask
& ~(crypto_tfm_ctx_alignment() - 1);
363 return len
+ type_obj
->ctxsize(alg
, type
, mask
);
365 switch (alg
->cra_flags
& CRYPTO_ALG_TYPE_MASK
) {
369 case CRYPTO_ALG_TYPE_CIPHER
:
370 len
+= crypto_cipher_ctxsize(alg
);
373 case CRYPTO_ALG_TYPE_COMPRESS
:
374 len
+= crypto_compress_ctxsize(alg
);
381 void crypto_shoot_alg(struct crypto_alg
*alg
)
383 down_write(&crypto_alg_sem
);
384 alg
->cra_flags
|= CRYPTO_ALG_DYING
;
385 up_write(&crypto_alg_sem
);
387 EXPORT_SYMBOL_GPL(crypto_shoot_alg
);
389 struct crypto_tfm
*__crypto_alloc_tfmgfp(struct crypto_alg
*alg
, u32 type
,
392 struct crypto_tfm
*tfm
= NULL
;
393 unsigned int tfm_size
;
396 tfm_size
= sizeof(*tfm
) + crypto_ctxsize(alg
, type
, mask
);
397 tfm
= kzalloc(tfm_size
, gfp
);
401 tfm
->__crt_alg
= alg
;
402 refcount_set(&tfm
->refcnt
, 1);
404 if (!tfm
->exit
&& alg
->cra_init
&& (err
= alg
->cra_init(tfm
)))
405 goto cra_init_failed
;
410 crypto_exit_ops(tfm
);
412 crypto_shoot_alg(alg
);
419 EXPORT_SYMBOL_GPL(__crypto_alloc_tfmgfp
);
421 struct crypto_tfm
*__crypto_alloc_tfm(struct crypto_alg
*alg
, u32 type
,
424 return __crypto_alloc_tfmgfp(alg
, type
, mask
, GFP_KERNEL
);
426 EXPORT_SYMBOL_GPL(__crypto_alloc_tfm
);
429 * crypto_alloc_base - Locate algorithm and allocate transform
430 * @alg_name: Name of algorithm
431 * @type: Type of algorithm
432 * @mask: Mask for type comparison
434 * This function should not be used by new algorithm types.
435 * Please use crypto_alloc_tfm instead.
437 * crypto_alloc_base() will first attempt to locate an already loaded
438 * algorithm. If that fails and the kernel supports dynamically loadable
439 * modules, it will then attempt to load a module of the same name or
440 * alias. If that fails it will send a query to any loaded crypto manager
441 * to construct an algorithm on the fly. A refcount is grabbed on the
442 * algorithm which is then associated with the new transform.
444 * The returned transform is of a non-determinate type. Most people
445 * should use one of the more specific allocation functions such as
446 * crypto_alloc_skcipher().
448 * In case of error the return value is an error pointer.
450 struct crypto_tfm
*crypto_alloc_base(const char *alg_name
, u32 type
, u32 mask
)
452 struct crypto_tfm
*tfm
;
456 struct crypto_alg
*alg
;
458 alg
= crypto_alg_mod_lookup(alg_name
, type
, mask
);
464 tfm
= __crypto_alloc_tfm(alg
, type
, mask
);
474 if (fatal_signal_pending(current
)) {
482 EXPORT_SYMBOL_GPL(crypto_alloc_base
);
484 static void *crypto_alloc_tfmmem(struct crypto_alg
*alg
,
485 const struct crypto_type
*frontend
, int node
,
488 struct crypto_tfm
*tfm
;
489 unsigned int tfmsize
;
493 tfmsize
= frontend
->tfmsize
;
494 total
= tfmsize
+ sizeof(*tfm
) + frontend
->extsize(alg
);
496 mem
= kzalloc_node(total
, gfp
, node
);
498 return ERR_PTR(-ENOMEM
);
500 tfm
= (struct crypto_tfm
*)(mem
+ tfmsize
);
501 tfm
->__crt_alg
= alg
;
503 refcount_set(&tfm
->refcnt
, 1);
508 void *crypto_create_tfm_node(struct crypto_alg
*alg
,
509 const struct crypto_type
*frontend
,
512 struct crypto_tfm
*tfm
;
516 mem
= crypto_alloc_tfmmem(alg
, frontend
, node
, GFP_KERNEL
);
520 tfm
= (struct crypto_tfm
*)(mem
+ frontend
->tfmsize
);
522 err
= frontend
->init_tfm(tfm
);
526 if (!tfm
->exit
&& alg
->cra_init
&& (err
= alg
->cra_init(tfm
)))
527 goto cra_init_failed
;
532 crypto_exit_ops(tfm
);
535 crypto_shoot_alg(alg
);
541 EXPORT_SYMBOL_GPL(crypto_create_tfm_node
);
543 void *crypto_clone_tfm(const struct crypto_type
*frontend
,
544 struct crypto_tfm
*otfm
)
546 struct crypto_alg
*alg
= otfm
->__crt_alg
;
547 struct crypto_tfm
*tfm
;
550 mem
= ERR_PTR(-ESTALE
);
551 if (unlikely(!crypto_mod_get(alg
)))
554 mem
= crypto_alloc_tfmmem(alg
, frontend
, otfm
->node
, GFP_ATOMIC
);
560 tfm
= (struct crypto_tfm
*)(mem
+ frontend
->tfmsize
);
561 tfm
->crt_flags
= otfm
->crt_flags
;
562 tfm
->exit
= otfm
->exit
;
567 EXPORT_SYMBOL_GPL(crypto_clone_tfm
);
569 struct crypto_alg
*crypto_find_alg(const char *alg_name
,
570 const struct crypto_type
*frontend
,
574 type
&= frontend
->maskclear
;
575 mask
&= frontend
->maskclear
;
576 type
|= frontend
->type
;
577 mask
|= frontend
->maskset
;
580 return crypto_alg_mod_lookup(alg_name
, type
, mask
);
582 EXPORT_SYMBOL_GPL(crypto_find_alg
);
585 * crypto_alloc_tfm_node - Locate algorithm and allocate transform
586 * @alg_name: Name of algorithm
587 * @frontend: Frontend algorithm type
588 * @type: Type of algorithm
589 * @mask: Mask for type comparison
590 * @node: NUMA node in which users desire to put requests, if node is
591 * NUMA_NO_NODE, it means users have no special requirement.
593 * crypto_alloc_tfm() will first attempt to locate an already loaded
594 * algorithm. If that fails and the kernel supports dynamically loadable
595 * modules, it will then attempt to load a module of the same name or
596 * alias. If that fails it will send a query to any loaded crypto manager
597 * to construct an algorithm on the fly. A refcount is grabbed on the
598 * algorithm which is then associated with the new transform.
600 * The returned transform is of a non-determinate type. Most people
601 * should use one of the more specific allocation functions such as
602 * crypto_alloc_skcipher().
604 * In case of error the return value is an error pointer.
607 void *crypto_alloc_tfm_node(const char *alg_name
,
608 const struct crypto_type
*frontend
, u32 type
, u32 mask
,
615 struct crypto_alg
*alg
;
617 alg
= crypto_find_alg(alg_name
, frontend
, type
, mask
);
623 tfm
= crypto_create_tfm_node(alg
, frontend
, node
);
633 if (fatal_signal_pending(current
)) {
641 EXPORT_SYMBOL_GPL(crypto_alloc_tfm_node
);
644 * crypto_destroy_tfm - Free crypto transform
645 * @mem: Start of tfm slab
646 * @tfm: Transform to free
648 * This function frees up the transform and any associated resources,
649 * then drops the refcount on the associated algorithm.
651 void crypto_destroy_tfm(void *mem
, struct crypto_tfm
*tfm
)
653 struct crypto_alg
*alg
;
655 if (IS_ERR_OR_NULL(mem
))
658 if (!refcount_dec_and_test(&tfm
->refcnt
))
660 alg
= tfm
->__crt_alg
;
662 if (!tfm
->exit
&& alg
->cra_exit
)
664 crypto_exit_ops(tfm
);
666 kfree_sensitive(mem
);
668 EXPORT_SYMBOL_GPL(crypto_destroy_tfm
);
670 int crypto_has_alg(const char *name
, u32 type
, u32 mask
)
673 struct crypto_alg
*alg
= crypto_alg_mod_lookup(name
, type
, mask
);
682 EXPORT_SYMBOL_GPL(crypto_has_alg
);
684 void crypto_req_done(void *data
, int err
)
686 struct crypto_wait
*wait
= data
;
688 if (err
== -EINPROGRESS
)
692 complete(&wait
->completion
);
694 EXPORT_SYMBOL_GPL(crypto_req_done
);
696 MODULE_DESCRIPTION("Cryptographic core API");
697 MODULE_LICENSE("GPL");